*{
  margin: 0;
  padding: 0;
}
body{
  background:#ececec;
}
li{
list-style: none;
  font-size: 14px;
  a{
    color: #aaa;
    text-decoration: none;
  }
  a:hover{
    color: #ececec;
  }
}
@mixin lr($l:auto,$r:auto){
  margin-left: $l;margin-right: $r;
}
.top{
  width:1920px;
  height: 120px;
  background: #000;
  .top-a{
    overflow: hidden;
    box-sizing: border-box;
    width: 1220px;height: 120px;
    @include lr;
    background: url("../images/logo.gif")no-repeat 0px center;
    span{
      float: right;
      margin-right: 50px;
    }
    button{
      margin-top: 40px;
      margin-right: 30px;
      float: right;
      width: 120px;
      height: 35px;
      color: #ececec;
      background:#000000;
      border: 1px solid #999;
      border-radius: 2px;
    }

    ul{
      padding-left:250px;
      float: left;
      @include lr;
      width: 760px;
      li{
        display: inline-block;
        margin-right:30px;
        line-height: 120px;
      }
    }
  }
}